This is a trimming device mostly used in combination with an E-size high-speed color printer, which was developed to allow speedy and efficient negative-film-based printing procedures for trimming enlargement orders.
When meeting orders for color print enlargement with an instruction for trimming by a customer, designation of only a specific area of a frame, usually negative film, for enlargement, color labs have been accepting it for the sizes larger than E-size (E-size 82.times.117 mm, L size 89.times.127 mm, or similar sizes) because it has been extremely difficult to achieve this trimming enlargement for the said E-size with an existing high-speed color printer.
As the primary condition, a printer capable of trimming enlargement must be equipped with a continuous variable magnification device. The second condition is that the printer be devised so that the operator can visually check the trimming area of the original film frame.
Accordingly, a photographic printer with variable magnification ability is provided with a viewer used for trimming confirmation.
In terms of the structure of this kind of viewer, two representative examples of the printer models with current viewer facility in practical use are shown in FIGS. 10 and 11.
FIG. 10 illustrates an existing printer pivoting around its optical system. Its configuration includes a negative carrier 40A to hold the negative frame usually, but sometimes transparency for positive-to-positive print, an illuminator unit 90A consisting of a lamp 91 to illuminate the negative and a condenser lens 92, a projection lens 50A to blow up the negative frame so that an enlarged image is formed on the print image plane 73, and an exposure shutter 62; the latter two, 50A and 62 are contained in a leakage-free housing together with the aforementioned 40A, which are designed so that the light from the illuminator unit 90 doesn't reach the print image plane for exposure and no light leakage is caused, except that the shutter 62 opens.
When it is necessary to check the print area of a frame as the trimming process by moving the negative on the negative carrier 40A to a desired position, the operator can relocate the mirror 74 from A to B to confirm the projected image on the viewer screen 76 by opening the said exposure shutter 62 and the screen shutter 77 located near the viewer screen 76; this is for completely shielding the projection light from being delivered to the photo sensitized material, viz., print paper, on the print image plane. Through this viewer monitoring, the operator is also allowed to further shift the position of the negative on the carrier or to change the magnification, so that he can obtain a trimming image of a desired size.
The indicator markings corresponding to the masking frame on the image-forming plane, are found on the screen. Thus, the operator can observe with his eyes which portion of the negative frame is projected within the mask.
After completion of viewer checking, the exposure shutter and the screen shutter are closed, and the mirror 74 is returned from B to A position. Now the preparations before exposure are complete.
Next an explanation on the model indicated in FIG. 11 is given below. This printer allows a more direct viewing from the print image forming plane. In its construction, a print plane shutter 81 is provided on the negative side of the print image plane, and while the said shutter 81 is closed, the negative frame specified for trimming is projected on the rear surface of the shutter within the area corresponding to the masking frame indicated on the screen (rear side). Now the operator can view the projected image, directly or through a separate viewer screen 76; in the latter case, a secondary projection method is employed, that is, the image projected on the shutter is reflected for secondary reflection on the mirror 79, and then transmitted to the viewer screen.
When confirming the projected image through this type of viewer shown in FIG. 11, first close the print plane shutter 81, and open the exposure shutter 62 and the viewer shutter 77A. Then the image projected on the print plane shutter 81 can be monitored. After the use of the viewer, close the viewer shutter 77A and the exposure shutter, and then open the print plane shutter 81 to make the print paper ready for exposure. As compared to the model indicated in FIG. 10, this printer doesn't need mirror rotation, but has an increased number of shutters.
Further, of late, a model is also available that catches the projected image with a CCD camera, in place of the conventional optical viewer, to display it on a monitor screen. In this case, the image projected on the viewer screen as in FIG. 10, or the projected image on the print plane shutter as in FIG. 11, is monitored through the lens of the CCD camera. With this new type of printer, as the operator is not required to confirm the projected image from the outside of the machine, neither a screen unit (FIG. 10 case) nor a direct-view window (FIG. 11 case) are necessary, further, there is no need of such aids as a screen shutter or a viewer shutter.
However, ON/OFF control of the exposure shutter, control of the mirror rotation, ON/OFF control of the screen shutter, etc. are required.
In any one of those cases of the existing printers, it is necessary to check in advance the state of trimming of the negative frame with the aid of a viewer function, simultaneously requiring a dedicated mechanism and relevant controls. This has been lowering the printing efficiency to a marked degree.
Particularly, the print plane shutter, rotary mirror, screen shutter, viewer shutter, etc. cannot avoid being designed extremely large in size, further, it additionally takes several seconds to complete the operation of each device. Accordingly this leads to the need of several tens of seconds or several minutes if all the other trimming processes are included.
Under this situation, a trimming job has so far been undertaken only in the case of orders mainly for specific large-size print production. If this trimming is applied to E-size print, especially re-order printing of E-size, called the NP print, it would necessitate considerable time and labor, which at present hinders its actual application.